1. Field of the Invention
The present invention relates to a display device, and more particularly, to a Three-Dimensional (3D) image display device and a driving method thereof, which display an image three-dimensionally.
2. Discussion of the Related Art
3D image display devices three-dimensionally display an image with characteristic where perspective is given in combining different image signals discerned by two eyes.
Such a 3D image display technique is largely categorized into a stereoscopic technique, a volumetric technique, and a holographic technique.
Among these techniques, the stereoscopic technique is again categorized into a glasses technique and a glassesless technique. Recently, the glassesless technique is being actively researched.
The glassesless technique is again categorized into a lenticular lens technique and a parallax barrier technique using a parallax barrier.
Recently, as disclosed in Korea Patent Application No. 10-2008-0070497, a method is being developed where a display device tracks a viewer's motion through eye-tracking, and varies the image transmission effect of a barrier panel according to the tracked position of the viewer, thereby enabling the viewer to watch a 3D image from an orthoscopic zone even when moving from a current position to another position.
FIG. 1 is an exemplary diagram for describing a state where a related art 3D image display device is using an eye-tracking scheme.
In a related art 3D image display device 10, a barrier panel including a parallax barrier or a lenticular lens is disposed in the front of a panel in a sheet type or the like, and thus respectively supplies different images to a user's left and right eyes to realize a 3D image.
FIG. 1 illustrates the 3D image display device 10 that displays a 3D image with nine views, and particularly illustrates a 3D image display device including a barrier panel where light transmission characteristic varies according to a voltage application scheme. Herein, for example, the barrier panel is configured with a liquid crystal electric field lens, and includes a switchable liquid crystal lens or a switchable barrier where a light transmitting direction varies according to the voltage application scheme.
The related art 3D image display device 10 of FIG. 1 tracks a viewer's position with an image collector 20 for eye-tracking, changes a voltage application scheme for the barrier panel to vary the light transmission characteristic of the barrier panel according to the tracked position of the viewer, and thus allows the tracked position to correspond to an orthoscopic zone, thereby enabling the viewer to view a normal 3D image.
Such an eye-tracking glassesless 3D image display device checks a view formed at the center thereof, thereby detecting a difference between a center point detected by the 3D image display device and a center point discerned by the viewer.
A method, which detects the difference between the center point detected by the 3D image display device and the center point discerned by the viewer, is performed through an operation where a measurer (manufacturer) directly measures the number of a corresponding view measured from the center point to check a view number in the center, namely, the number of center views, at a stage of manufacturing a 3D image display device.
A view map created by the method is predetermined as certain relative positions from the 3D image display device, in which case the position of the center view (being the center point) is also predetermined. Therefore, when a viewer actually watches 3D images displayed by the 3D image display device, the 3D image display device varies the light transmission characteristic of the barrier panel according to the viewer's position, by using the viewer's position coordinates tracked by the image collector and the view map predetermined through the operation. Accordingly, viewers can watch normal 3D images from an orthoscopic zone at any time.